SINCE dumping his age-appropriate wife, Susan Weber Soros, 63, in 2005, billionaire George Soros, 77, has turned to younger women to satisfy his companionship needs. Sources say the financier and founder of moveon.org has “a fondness for girls in their early 20s. He has entertained many young lovelies at his house in Southampton and is currently dating 22-year-old Russian playgirl Marina Zelle.” A rep for Soros declined to comment.